* Dont use raise_error by itself (avoids warning)
* Add coverage for AccountFilter
* Improve coverage and refactor for Subscription#lease_seconds
* Improve coverage and refactor for NotificationMailer
* Simplify assignment of min/max threshold on subscription
* add annotate to Gemfile
* rails g annotate:install
* configure annotate_models
* add schema info to models
* fix rubocop to add frozen_string_literal